1. Technical Field
Aspects of the present invention relate to a management system for managing a communication device that communicates with various type of devices through a network using a plurality of types of protocols.
2. Description of Related Art
An internet protocol (IP) is widely used for communicating with various types of devices through a network. Examples of a network system in which the internet protocol is used in data communication are disclosed in Japanese Patent Provisional Publications Nos. 2004-32699, 2000-183874, and 2001-034434.
The internet protocol is now moving from IPv4 (Internet Protocol version 4) to IPv6 (Internet Protocol version 6). Therefore, in many cases, devices using IPv4 and devices using IPv6 are mixed in a single network environment. For this reason, recently, communication devices capable of using both of the IPv4 and IPv6 are developed and proposed. Typically, such a device is configured such that an ON/OFF state of each of the function of IPv4 communication and the function of IPv6 communication can be controlled.
In the communication based on the internet protocol, to communicate with a certain device (e.g., a server), a communication device sends a packet, containing an IP address or a domain name of the certain device, to a network. That is, the IP address or the domain name contained in the packet designates a destination (a destination device) to which the packet is sent. In the communication between the communication device and a destination device, if an IP address based on an IPv4 format is registered in the communication device as setting data regarding the destination device, while the IPv4 communication function of the communication device is in an OFF state, the communication device can not communicate with the destination device.
In the communication in which the destination device is designated by a domain name, the communication device accesses a DNS (Domain Name System) server to change the domain name to an IP address. In such a case, if the ON/OFF states of the IPv4 and IPv6 communication functions of the communication device do not match with the IP protocol of the DNS server, the communication device can not access the DNS server.
That is, in the communication in which a communication device having the IPv4 and IPv6 communication functions is involved, there is a possibility that the ON/OFF states of the IPv4 and IPv6 communication functions of the communication device do not match with the setting data (e.g. destination addresses of destination devices) stored in the communication device. If such inconsistency arises between the ON/OFF states of the IPv4 and IPv6 communication functions and the setting data regarding the communication stored in the communication device, the communication in which the communication device is involved becomes unsuccessful.
If the setting data of a communication device having the IPv4 and IPv6 communication functions is changed, a possibility arises that a device, which is capable of using only one of the IPv4 and IPv6 functions, will become unable to communicate with the communication device.
In other words, if inconsistency arises between a communication function of a destination device and a protocol which a communication device uses to communicate with the destination device, the communication between the communication device and the destination device will become unsuccessful.